And Murdo Fraser – a Tory member of the Scottish Parliament – said people may not even know what to name a political entity just made up of England, Wales and Northern Ireland.

Leading academic Dr Walker – a Scot who has lived here for 20 years – added that the Union would never be the same again, even if independence is rejected.

He was speaking at a one-day QUB conference looking at the impact of the referendum on Northern Ireland.

Dr Walker, who is based at the Queen's School of Politics, International Studies and Philosophy, said: "If there is a 'Yes' vote, clearly it's going to lead to the break-up of the UK, and that is very far-reaching, especially for unionists. There will be a crisis for unionism if it happens."

And he believes the Irish government will be watching events closely to see how the result will affect links between it and Westminster. Even if there is a 'No' result in September, Mr Walker added: "Things will never be the same again" as more powers will still be handed over from Westminster to Edinburgh.

Conservative MSP Mr Fraser is a supporter of the Better Together campaign for a 'No' vote and he said there was a "lot of uncertainty around the consequences of a 'Yes' vote".

Scottish independence would leave the rest of the United Kingdom in a very peculiar situation, he said. As well as issues over the actual name of a United Kingdom without Scotland, there would be a new imbalance – a very large England, with Wales and Northern Ireland as two small "adjuncts".

Mr Fraser said many people in Northern Ireland had a "strong affinity" with Scotland and he believed the break-up of the Union could be a "very fatal blow" for unionists.

Even with a 'No' vote, Mr Fraser said the UK could become more "federal" in response to countries looking for less power being wielded centrally by London.

Around 50 people attended the Scotland's Choice: Reshaping Relationships? conference, including Ulster Unionist MLA Danny Kinahan. He said he did not think Scottish independence would become a threat to Northern Ireland's position in the UK "but there would be those who would want to do that".

Mr Kinahan, who said he was attending in a personal capacity and not as a member of the Ulster Unionist Party, added: "I'm for the Union and I support the Better Together campaign.

"If it is 'Yes' then we have to set down how we keep the benefits of the Union."

Factfile

An ICM poll released earlier this month suggested that nearly half (42%) of Scottish families are divided on whether the country should become independent.

The poll, for the Scotland on Sunday newspaper, also exposed significant fears that Scotland would remain divided after September's referendum.

Of the 1,003 people surveyed, 36% planned to vote in favour of independence, while 43% opposed it and 21% of voters were undecided.